Ukrainian SSR

The Ukrainian SSR was a socialist constituent republic of the Soviet Union which existed from 1919 to 1991. The Ukrainian SSR was formed during the Russian Civil War in 1919, when the Bolsheviks took over the Ukrainian National Republic from Szymon Petlyura's Ukrainian nationalists. Western Ukraine (Lviv and other cities) was annexed by the USSR in 1939 during the invasion of Poland, and the Crimea was granted to the Ukrainian SSR in the 1950s. In 1991, the fall of the USSR led to the independence of Ukraine, and a new constitution was ratified in 1996.